Mentzelia obscura
Mentzelia ravenii
Pacific blazing star
grass blazingstar, Raven's blazingstar
persisting;
petiole present or absent;
blade linear-lanceolate to linear, margins usually irregularly deeply lobed, lobes pointed.
persisting;
petiole present or absent;
blade linear-lanceolate, margins deeply to shallowly lobed.
petiole absent;
blade ovate-lanceolate to linear, to 15(–22) cm, margins few-lobed or entire.
petiole absent;
blade ovate-lanceolate to lanceolate, to 18 cm, margins deeply lobed to dentate.
green, ovate to ovate-lanceolate, 2.9–8.2 × 1.1–1.9 mm, width 1/8–1/2 length, not concealing capsule, margins entire.
green with prominent white base usually conspicuously extending outwards from midvein, ovate, 5.6–8.4 × 1.8–3.9 mm, width 1/5–2/3 length, not concealing capsule, margins 3–5-lobed.
sepals 2–6 mm;
petals yellow to orange proximally, yellow distally, 3–8 mm, apex rounded or acute apex;
stamens 20–40, 2–7 mm, filaments monomorphic, filiform, unlobed;
styles 2–6 mm.
sepals 2–6 mm;
petals orange proximally, yellow distally, 5–11(–13) mm, apex retuse;
stamens 20+, 3–7 mm, filaments monomorphic, filiform, unlobed;
styles 3.5–8 mm.
clavate, 11–31 × 1.5–3 mm, axillary curved to 250° at maturity, usually inconspicuously longitudinally ribbed.
clavate, 8–23 × 2–3 mm, axillary curved to 45° at maturity, usually inconspicuously longitudinally ribbed.
15–50, in 2+ rows distal to mid fruit, tan, usually not, occasionally sparsely, dark-mottled, usually irregularly polygonal, occasionally triangular prisms proximal to mid fruit, surface colliculate under 10x magnification; recurved flap over hilum absent;
seed coat cell outer periclinal wall domed, domes on seed edges less than 1/2 as tall as wide at maturity.
15–30, in 2+ rows distal to mid fruit, tan, dark-mottled, usually irregularly polygonal, occasionally triangular prisms proximal to mid fruit, surface tuberculate under 10x magnification; recurved flap over hilum absent;
seed coat cell outer periclinal wall domed, domes on seed edges more than or equal to 1/2 as tall as wide at maturity.
= 36.
= 36.
Mentzelia obscura
Mentzelia ravenii
Mentzelia obscura is morphologically intermediate to M. desertorum and M. albicaulis and is known to occur in mixed populations with both species. Reliable discrimination among these species usually requires mature seeds.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Mentzelia ravenii is narrowly distributed, with most populations limited to desert foothills on the northern edge of the San Gabriel Mountains in northeastern Los Angeles County. Populations of M. ravenii with relatively large flowers with yellow petals are often found growing under desert shrubs in mixed populations with M. veatchiana, which has relatively small flowers with orange petals in this area. A few tetraploid populations from western Riverside County have also been called M. ravenii (J. E. Zavortink 1966); further work is needed to confirm that these represent the same species. See 72. M. gracilenta for discussion of similarities it shares with M. ravenii.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
WildflowerSearch
iNaturalist
USDA Plants Database
